106 i*. T. CLEVE, SYNOPSIS OF tHE NAVlCULOin DIATOMS. 



( Ends snbcapitate A\ mida Pant. 



\ — acute 3. 



[StriiB abont 12 in 0,0 1 mm N. ludda Pant. 



I — — 17 — K. Schmidtii Lägst. 



3- j _ — 24 — 2\. Acua Cl. 



I _ — 30 — 4. 



J Longitudinal stris doser tlian tlie transverse K. fvsiformis Gbun. 



I — — more distaiit N. FrauenfehUi Grcn. 



. j Ends rostrate ^" crassirosMs Geun. 



' \ — obtase or trunoate t>. 



„ I Terminal fissures in contrary directions 7. 



'■ \ — — indistinot iV. Lineola Geun. 



„ I Stris all parallel N. parallelistriata Pant. 



' ' \ Median stria radiate N heteroflexa Pant. 



1. N. fusiformis Grun. (1877). — V. iiarrow, lanceolate, gradually tapering from the midcUe 

 to the acute ends. L. O.i 15 to 0,i r, ; B. 0, 01 mm. Central pores very approximate. Strise trans- 

 verse, 33 in 0,01 mm., longitudinal 36 in 0,oi mm. — Bcrkelcya Fusidium G-Rux. Hedw. I.sfi7 p. 17. 

 Amphipleura danica KtJTZ Bac. p. 103 Pl. XXX f. 38 (1844)? N. fus. Gkun. M. .T. 1877 p. 178 

 Pl. CXCV f. 11. 



Marine: Honduras (Grun.). 



Var. ostrearia Gaillon (1820). — L. 0,o63 to 0,o73; B. 0,oo6 to 0,oo7 mm. Striaä transverse 

 36 in 0,01 mm. — Vibrio osfrearius Gaillon (accord. to Grun.). — Nar. ostrearia TnrT[). Diet. å''hist. 

 nat. II Pl. I f . 2 (accord. to Grun.). N. fusif. v. ostrearia Grun. M. M. J. 1877 p. 178 Pl. CXCV 

 f. 12. V. H. Syn. Pl. XIV f. 33. 



Marine: North Sea (West coast of Sweden)! Loire infér. (Grun.), Marseille (Grun.), Triest (Grun.). 



This species lives on oyster-beds and according to Bornet the oysters become greenish by 

 feeding on this diatom. Living frustules have two chromatophore-plates along the connecting zoue. 

 The eell-sap has, especially towards the ends, a peculiar blue colour. 



2. N. Franenfeldii Grun. (1863). — V. lanceolate. L. 0,i to 0,i6; B. 0,oi9 to 0,025 mm. 

 Central pores very approximate. Transverse striai 29 in 0, 01 mm., longitudinal more distant. — 

 Amphipleura Franenfeldii Grux. Verh. 1S63 p. 144 Pl. V f. 3. N. Frauenf. Grux. M. M. J. 1877 p. 179. 



Marine: Indian Ocean (Grun.). 



3. N, imda Pant. (1889). — V. narrow, lanceolate, with subcapitate ends. L. 0,0.37; B. O.007 

 mm. StricE not observed. — Pant. II p. 51 Pl. VI f 108. 



Brackish water: Hungary, fossil (Pant.). 



This species is unknown to me and the description and figure are not sufficient for diagnosis. 



4. N. Acus Cl. N. Sp. — V. narrow, lanceolate, acute. L. 0,09; B. 0,oo9 mm. Central 

 pores approximate. Terminal fissures elongated. Axial and central areas indistinct. Stria; 24 to 

 25 in 0,0 1 mm., equidistant, in the middle .slightly radiate, elsewhere transverse, or nearly so — 

 Pl. III f. 29, 30. 



Marine: Balearic Islands! 



As N. Acus Cl. 1880 (A. D.) is the same as N. inornafa Grun. the name Acus may be used 

 for this form, ^Yhich differs from JSf. fusoides Grun. (1880) by the absence of longitudinal lines and 

 by its indistinct area. 



5. N. Schmidtii Lägst. (1876). — V. narrow. lanceolate, with somewhat obtuse ends. 

 L. 0,06 to 0,074; B. 0,009 to 0,011 mm. Central pores approximate. Sh-iae about 17 in 0, 01 mm., 

 transverse. — N. (without name) A. S. N. S. D. Pl. III f 7, 8 (1874). N. Schni. Ldt. Boh. D. p. 45. 



Marine: Bohuslän (Ldt). 



I do not know this species, which seems doubtful. The fig. in A. S. is not sufficient, and 

 the description of Lagerstedt may belong to some form of Nav. (Schizonema) ramosissima. The 



